The risk and development of work disability among individuals with gambling disorder: a longitudinal case-cohort study in Sweden

BACKGROUND

This longitudinal register study aimed to investigate the association between gambling disorder (GD) and work disability and to map work disability in subgroups of individuals with GD, three years before and three years after diagnosis.

METHODS

We included individuals aged 19-62 with GD between 2005 and 2018 (n = 2830; 71.1% men, mean age: 35.1) and a matched comparison cohort (n = 28 300). Work disability was operationalized as the aggregated net days of sickness absence and disability pension. Generalized estimating equation models were used to calculate adjusted odds ratios (AORs) and 95% confidence intervals (CIs) for the risk of long-term work disability (>90 days of work disability/year). Secondly, we conducted Group-based Trajectory Models on days of work disability.

RESULTS

Individuals with GD showed a four-year increased risk of long-term work disability compared to the matched cohort, peaking at the time of diagnosis (AOR = 1.89; CI 1.67-2.13). Four trajectory groups of work disability days were identified: constant low (60.3%, 5.6-11.2 days), low and increasing (11.4%, 11.8-152.5 days), medium-high and decreasing (11.1%, 65.1-110 days), and constant high (17.1%, 264-331 days). Individuals who were females, older, with prior psychiatric diagnosis, and had been dispensed a psychotropic medication, particularly antidepressants, were more likely to be assigned to groups other than the constant low.

CONCLUSION

Individuals with GD have an increased risk of work disability which may add financial and social pressure and is an additional incentive for earlier detection and prevention of GD.

Medication utilization in traumatic brain injury patients-insights from a population-based matched cohort study

Introduction

Traumatic brain injury (TBI) is associated with health problems across multiple domains and TBI patients are reported to have high rates of medication use. However, prior evidence is thin due to methodological limitations. Our aim was thus to examine the use of a wide spectrum of medications prescribed to address pain and somatic conditions in a population-based cohort of TBI patients, and to compare this to a sex- and age-matched cohort. We also examined how patient factors such as sex, age, and TBI severity were associated with medication use.

Methods

We assessed Swedish nationwide registers to include all individuals treated for TBI in hospitals or specialist outpatient care between 2006 and 2012. We examined dispensed prescriptions for eight different non-psychotropic medication classes for the 12 months before, and 12 months after, the TBI. We applied a fixed-effects model to compare TBI patients with the matched population cohort. We also stratified TBI patients by sex, age, TBI severity and carried out comparisons using a generalized linear model.

Results

We identified 239,425 individuals with an incident TBI and 239,425 matched individuals. TBI patients were more likely to use any medication [Odds ratio (OR) = 2.03, 95% Confidence Interval (CI) = 2.00-2.05], to present with polypharmacy (OR = 1.96, 95% CI = 1.90-2.02), and to use each of the eight medication classes before their TBI, as compared to the matched population cohort. Following the TBI, TBI patients were more likely to use any medication (OR = 1.83, 95% CI = 1.80-1.86), to present with polypharmacy (OR = 1.74, 95% CI = 1.67-1.80), and to use all medication classes, although differences were attenuated. However, differences increased for antibiotics/antivirals (OR = 2.02, 95% CI = 1.99-2.05) and NSAIDs/antirheumatics (OR = 1.62, 95% CI = 1.59-1.65) post-TBI. We also found that females and older patients were more likely to use medications after their TBI than males and younger patients, respectively. Patients with more severe TBIs demonstrated increased use of antibiotics/ antivirals and NSAIDs/antirheumatics than those with less severe TBIs.

Discussion

Taken together, our results point to poor overall health in TBI patients, suggesting that medical follow-up should be routine, particularly in females with TBI, and include a review of medication use to address potential polypharmacy.

The genetics of gaming: A longitudinal twin study

Background

Gaming is a popular past-time activity among children and adolescents, but it there is also a possible link to negative consequences such as psychological distress and lowered academic achievement. However, there are fundamental knowledge gaps remaining regarding central characteristics of gaming such as heritability, stability over time, and sex differences. We examined the genetic and environmental contribution to gaming behavior, including sex differences, continuity and change, in a longitudinal cohort of twins.

Methods

This is the first longitudinal twin study on gaming, involving 32,006 twins in Sweden. Parents were asked about the twins' gaming at ages 9, 15 and 18. We used univariate and multivariate twin analyses to estimate the relative contribution of genetic and environmental influences at each time-point as well as across time. Sex-differences were also explored.

Results

The results showed large sex differences, where genetics explained more of the variance for boys (31.3%-62.5% depending on age) than for girls (19.4%-23.4%). Genetic factors explained an increasing amount of the variance for boys (31.3% at age 9, 62.5% at age 15 and 53.9% at age 18). Shared environmental factors explained a larger proportion of the variance among girls, which remained relatively stable over time (70.5% at age 9, 61.8% at age 15 and 60.5% at age 18). The results also indicated that most of the variance came from genetic and environmental sources specific to each age.

Conclusions

Compared to many other behavioral phenotypes, such as gambling, gaming was relatively unstable with a large degree of genetic innovation. There were large sex differences in the contribution of genetic and environmental factors. This suggests that excessive gaming could be the result of age- and sex-specific genetic and environmental factors, and should be taken into account when mapping gaming behaviors, since these behaviors might be under continual etiological transformation.

Access to Rehabilitation After Hospitalization for Traumatic Brain Injury: A National Longitudinal Cohort Study in Sweden

BACKGROUND

Rehabilitation is suggested to improve outcomes following traumatic brain injury (TBI), however, the extent of access to rehabilitation among TBI patients remains unclear.

OBJECTIVE

To examine the level of access to rehabilitation after TBI, and its association with health and sociodemographic factors.

METHOD

We conducted a longitudinal cohort study using Swedish nationwide healthcare and sociodemographic registers. We identified 15 880 TBI patients ≥18 years hospitalized ≥3 days from 2008 to 2012 who were stratified into 3 severity groups; grade I (n = 1366; most severe), grade II (n = 5228), and grade III (n = 9268; least severe). We examined registered contacts with specialized rehabilitation or geriatric care (for patients ≥65 years) during the hospital stay, and/or within 1 year post-discharge. We performed a generalized linear model analysis to estimate the risk ratio (RR) for receiving specialized rehabilitation or geriatric care after a TBI based on sociodemographic and health factors.

RESULTS

Among TBI patients, 46/35% (grade I), 14/40% (grade II), and 5/18% (grade III) received specialized rehabilitation or geriatric care, respectively. Being currently employed or studying was positively associated (RR 1.7, 2.3), while living outside of a city area was negatively associated (RR 0.36, 0.79) with receiving specialized rehabilitation or geriatric care. Older age and a prior substance use disorder were negatively associated with receiving specialized rehabilitation (RR 0.51 and 0.81).

CONCLUSION

Our results suggest insufficient and unequal access to rehabilitation for TBI patients, highlighting the importance of organizing and standardizing post-TBI rehabilitation to meet the needs of patients, regardless of their age, socioeconomic status, or living area.

Development and Validation of a Prediction Tool for Reoffending Risk in Domestic Violence

Importance

Current risk assessment tools for domestic violence against family members were developed with small and selected samples, have low accuracy with few external validations, and do not report key performance measures.

Objective

To develop new tools to assess risk of reoffending among individuals who have perpetrated domestic violence.

Design, Setting, and Participants

This prognostic study investigated a national cohort of all individuals arrested for domestic violence between 1998 and 2013 in Sweden using information from multiple national registers, including National Crime Register, National Patient Register, Longitudinal Integrated Database for Health Insurance and Labour Market Studies Register, and Multi-Generation Register. Data were analyzed from August 2022 to June 2023.

Exposure

Arrest for domestic violence.

Main Outcomes and Measures

Prediction models were developed for 3 reoffending outcomes after arrest for domestic violence: conviction of a new violent crime (including domestic violence), conviction of any new crime, and rearrest for domestic violence at 1 year, 3 years, and 5 years. The prediction models were created using sociodemographic factors, criminological factors, and mental health status-related factors, linking data from multiple population-based longitudinal registers. Cox proportional hazard multivariable regression was used to develop prediction models and validate them in external samples. Key performance measures, including discrimination at prespecified cutoffs and calibration statistics, were investigated.

Results

The cohort included 27 456 individuals (mean [SD] age, 39.4 [11.6] years; 24 804 men [90.3%]) arrested for domestic violence, of whom 4222 (15.4%) reoffended and were convicted for a new violent crime during a mean (SD) follow-up of 26.5 (27.0) months, 9010 (32.8%) reoffended and were convicted for a new crime (mean [SD] follow-up, 22.4 [25.1] months), and 2080 (7.6%) were rearrested for domestic violence (mean [SD] follow-up, 25.7 [30.6] months). Prediction models were developed with sociodemographic, criminological, and mental health factors and showed good measures of discrimination and calibration for violent reoffending and any reoffending. The area under the receiver operating characteristic curve (AUC) for risk of violent reoffending was 0.75 (95% CI, 0.74-0.76) at 1 year, 0.76 (95% CI, 0.75-0.77) at 3 years, and 0.76 (95% CI, 0.75-0.77) 5 years. The AUC for risk of any reoffending was 0.76 (95% CI, 0.75-0.77) at 1 year and at 3 years and 0.76 (95% CI, 0.75-0.76) at 5 years. The model for domestic violence reoffending showed modest discrimination (C index, 0.63; 95% CI, 0.61-0.65) and good calibration. The validation models showed discrimination and calibration performance similar to those of derivation models for all 3 reoffending outcomes. The prediction models have been translated into 3 simple online risk calculators that are freely available to use.

Conclusions and Relevance

This prognostic study developed scalable, evidence-based prediction tools that could support decision-making in criminal justice systems, particularly at the arrest stage when identifying those at higher risk of reoffending and screening out individuals at low risk of reoffending. Furthermore, these tools can enhance treatment allocation by enabling criminal justice services to focus on modifiable risk factors identified in the tools for individuals at high risk of reoffending.

Risk of death by suicide following self-harm presentations to healthcare: development and validation of a multivariable clinical prediction rule (OxSATS)

BACKGROUND

Assessment of suicide risk in individuals who have self-harmed is common in emergency departments, but is often based on tools developed for other purposes.

OBJECTIVE

We developed and validated a predictive model for suicide following self-harm.

METHODS

We used data from Swedish population-based registers. A cohort of 53 172 individuals aged 10+ years, with healthcare episodes of self-harm, was split into development (37 523 individuals, of whom 391 died from suicide within 12 months) and validation (15 649 individuals, 178 suicides within 12 months) samples. We fitted a multivariable accelerated failure time model for the association between risk factors and time to suicide. The final model contains 11 factors: age, sex, and variables related to substance misuse, mental health and treatment, and history of self-harm. Transparent reporting of a multivariable prediction model for individual prognosis or diagnosis guidelines were followed for the design and reporting of this work.

FINDINGS

An 11-item risk model to predict suicide was developed using sociodemographic and clinical risk factors, and showed good discrimination (c-index 0.77, 95% CI 0.75 to 0.78) and calibration in external validation. For risk of suicide within 12 months, using a 1% cut-off, sensitivity was 82% (75% to 87%) and specificity was 54% (53% to 55%). A web-based risk calculator is available (Oxford Suicide Assessment Tool for Self-harm or OxSATS).

CONCLUSIONS

OxSATS accurately predicts 12-month risk of suicide. Further validations and linkage to effective interventions are required to examine clinical utility.

CLINICAL IMPLICATIONS

Using a clinical prediction score may assist clinical decision-making and resource allocation.

Associations between β-blockers and psychiatric and behavioural outcomes: A population-based cohort study of 1.4 million individuals in Sweden

BACKGROUND

β-blockers are widely used for treating cardiac conditions and are suggested for the treatment of anxiety and aggression, although research is conflicting and limited by methodological problems. In addition, β-blockers have been associated with precipitating other psychiatric disorders and suicidal behaviour, but findings are mixed. We aimed to examine associations between β-blockers and psychiatric and behavioural outcomes in a large population-based cohort in Sweden.

METHODS AND FINDINGS

We conducted a population-based longitudinal cohort study using Swedish nationwide high-quality healthcare, mortality, and crime registers. We included 1,400,766 individuals aged 15 years or older who had collected β-blocker prescriptions and followed them for 8 years between 2006 and 2013. We linked register data on dispensed β-blocker prescriptions with main outcomes, hospitalisations for psychiatric disorders (not including self-injurious behaviour or suicide attempts), suicidal behaviour (including deaths from suicide), and charges of violent crime. We applied within-individual Cox proportional hazards regression to compare periods on treatment with periods off treatment within each individual in order to reduce possible confounding by indication, as this model inherently adjusts for all stable confounders (e.g., genetics and health history). We also adjusted for age as a time-varying covariate. In further analyses, we adjusted by stated indications, prevalent users, cardiac severity, psychiatric and crime history, individual β-blockers, β-blocker selectivity and solubility, and use of other medications. In the cohort, 86.8% (n = 1,215,247) were 50 years and over, and 52.2% (n = 731,322) were women. During the study period, 6.9% (n = 96,801) of the β-blocker users were hospitalised for a psychiatric disorder, 0.7% (n = 9,960) presented with suicidal behaviour, and 0.7% (n = 9,405) were charged with a violent crime. There was heterogeneity in the direction of results; within-individual analyses showed that periods of β-blocker treatment were associated with reduced hazards of psychiatric hospitalisations (hazard ratio [HR]: 0.92, 95% confidence interval [CI]: 0.91 to 0.93, p < 0.001), charges of violent crime (HR: 0.87, 95% CI: 0.81 to 0.93, p < 0.001), and increased hazards of suicidal behaviour (HR: 1.08, 95% CI: 1.02 to 1.15, p = 0.012). After stratifying by diagnosis, reduced associations with psychiatric hospitalisations during β-blocker treatment were mainly driven by lower hospitalisation rates due to depressive (HR: 0.92, 95% CI: 0.89 to 0.96, p < 0.001) and psychotic disorders (HR: 0.89, 95% CI: 0.85 to 0.93, p < 0.001). Reduced associations with violent charges remained in most sensitivity analyses, while associations with psychiatric hospitalisations and suicidal behaviour were inconsistent. Limitations include that the within-individual model does not account for confounders that could change during treatment, unless measured and adjusted for in the model.

CONCLUSIONS

In this population-wide study, we found no consistent links between β-blockers and psychiatric outcomes. However, β-blockers were associated with reductions in violence, which remained in sensitivity analyses. The use of β-blockers to manage aggression and violence could be investigated further.

Comparative effect of metformin versus sulfonylureas with dementia and Parkinson's disease risk in US patients over 50 with type 2 diabetes mellitus

INTRODUCTION

Type 2 diabetes is a risk factor for dementia and Parkinson's disease (PD). Drug treatments for diabetes, such as metformin, could be used as novel treatments for these neurological conditions. Using electronic health records from the USA (OPTUM EHR) we aimed to assess the association of metformin with all-cause dementia, dementia subtypes and PD compared with sulfonylureas.

RESEARCH DESIGN AND METHODS

A new user comparator study design was conducted in patients ≥50 years old with diabetes who were new users of metformin or sulfonylureas between 2006 and 2018. Primary outcomes were all-cause dementia and PD. Secondary outcomes were Alzheimer's disease (AD), vascular dementia (VD) and mild cognitive impairment (MCI). Cox proportional hazards models with inverse probability of treatment weighting (IPTW) were used to estimate the HRs. Subanalyses included stratification by age, race, renal function, and glycemic control.

RESULTS

We identified 96 140 and 16 451 new users of metformin and sulfonylureas, respectively. Mean age was 66.4±8.2 years (48% male, 83% Caucasian). Over the 5-year follow-up, 3207 patients developed all-cause dementia (2256 (2.3%) metformin, 951 (5.8%) sulfonylurea users) and 760 patients developed PD (625 (0.7%) metformin, 135 (0.8%) sulfonylurea users). After IPTW, HRs for all-cause dementia and PD were 0.80 (95% CI 0.73 to 0.88) and 1.00 (95% CI 0.79 to 1.28). HRs for AD, VD and MCI were 0.81 (0.70-0.94), 0.79 (0.63-1.00) and 0.91 (0.79-1.04). Stronger associations were observed in patients who were younger (<75 years old), Caucasian, and with moderate renal function.

CONCLUSIONS

Metformin users compared with sulfonylurea users were associated with a lower risk of all-cause dementia, AD and VD but not with PD or MCI. Age and renal function modified risk reduction. Our findings support the hypothesis that metformin provides more neuroprotection for dementia than sulfonylureas but not for PD, but further work is required to assess causality.

Prediction of reoffending risk in men convicted of sexual offences: development and validation of novel and scalable risk assessment tools (OxRIS)

BACKGROUND

Current risk assessment tools have a limited evidence base with few validations, poor reporting of outcomes, and rarely include modifiable factors.

METHODS

We examined a national cohort of men convicted of sexual crimes in Sweden. We developed prediction models for three outcomes: violent (including sexual), any, and sexual reoffending. We used Cox proportional hazard regression to develop multivariable prediction models and validated these in an external sample. We reported discrimination and calibration statistics at prespecified cut-offs.

FINDINGS

We identified 16,231 men convicted of sexual offences, of whom 14.8% violently reoffended during a mean follow up of 38 months, 31.4% for any crime (34 months), and 3.6% for sexual crimes (42 months). Models for violent and any reoffending showed good discrimination and calibration. At 1, 3, and 5 years, the area under the curve (AUC) was 0.75-0.76 for violent reoffending and 0.74-0.75 for any reoffending. The prediction model for sexual reoffending showed modest discrimination (AUC = 0.67) and good calibration. We have generated three simple and web-based risk calculators, which are freely available.

INTERPRETATION

Scalable evidence-based risk assessment tools for sexual offenders in the criminal justice system and forensic mental health could assist decision-making and treatment allocation by identifying those at higher risk, and screening out low risk persons.

Associations between prisons and recidivism: A nationwide longitudinal study

Objectives

To examine differences in recidivism rates between different prisons using two designs—between-individual and within-individual—to account for confounding factors.

Methods

We examined recidivism rates among 37,891 individuals released from 44 Swedish prisons in three security levels, and who were followed from 2006 to 2013. We used longitudinal data from nationwide registers, including all convictions from district courts. First, we applied a between-individual design (Cox proportional hazards regression), comparing reconviction rates between individuals released from prisons within the same security level, while adjusting for a range of individual-level covariates. Second, we applied a within-individual design (stratified Cox proportional hazards regression), comparing rates of reconviction within the same individuals, i.e., we compared rates after release from one prison to the rates in the same individual after release from another prison, thus adjusting for all time-invariant confounders within each individual (e.g. genetics and early environment). We also adjusted for a range of time-varying individual-level covariates.

Results

Results showed differences in the hazard of recidivism between different prisons in between-individual analyses, with hazards ranging from 1.22 (1.05–1.43) to 4.99 (2.44–10.21). Results from within-individual analyses, which further adjusted for all time-invariant confounders, showed minimal differences between prisons, with hazards ranging from 0.95 (0.87–1.05) to 1.05 (0.95–1.16). Only small differences were found when violent and non-violent crimes were analyzed separately.

Conclusions

The study highlights the importance of research designs that more fully adjust for individual-level confounding factors to avoid over-interpretation of the variability in comparisons across prisons.

Psychotropic and pain medication use in individuals with traumatic brain injury-a Swedish total population cohort study of 240 000 persons

OBJECTIVE

To examine psychotropic and pain medication use in a population-based cohort of individuals with traumatic brain injury (TBI), and compare them with controls from similar backgrounds.

METHODS

We assessed Swedish nationwide registers to include all individuals diagnosed with incident TBI between 2006 and 2012 in hospitals or specialist outpatient care. Full siblings never diagnosed with TBI acted as controls. We examined dispensed prescriptions for psychotropic and pain medications for the 12 months before and after the TBI.

RESULTS

We identified 239 425 individuals with incident TBI, and 199 658 unaffected sibling controls. In the TBI cohort, 36.6% had collected at least one prescription for a psychotropic or pain medication in the 12 months before the TBI. In the 12 months after, medication use increased to 45.0%, an absolute rate increase of 8.4% (p<0.001). The largest post-TBI increases were found for opioids (from 16.3% to 21.6%, p<0.001), and non-opioid pain medications (from 20.3% to 26.6%, p<0.001). The majority of prescriptions were short-term; 20.6% of those prescribed opioids and 37.3% of those with benzodiazepines collected prescriptions for more than 6 months. Increased odds of any psychotropic or pain medication were associated with individuals before (OR: 1.62, 95% CI: 1.59 to 1.65), and after the TBI (OR: 2.30, 95% CI: 2.26 to 2.34) as compared with sibling controls, and ORs were consistently increased for all medication classes.

CONCLUSION

High rates of psychotropic and pain medications after a TBI suggest that medical follow-up should be routine and review medication use.

Associations between statin use and suicidality, depression, anxiety, and seizures: a Swedish total-population cohort study

BACKGROUND

Statins have shown both protective and adverse associations with neuropsychiatric outcomes. We aimed to examine the possible associations between statins and suicidality, depression, anxiety, and seizures.

METHODS

Using Swedish national registers, we linked data on dispensed statin prescriptions with data on unplanned (emergency) hospital visits or specialised outpatient care for four neuropsychiatric outcomes: suicidal behaviour (including deaths from suicide), depressive disorders, anxiety disorders, and seizures. We included all individuals in the registries who were dispensed statins and who were aged 15 years or older between Jan 1, 2006, and Dec 31, 2013. We applied a within-individual design using stratified Cox proportional hazards regression to compare the incidence of the defined outcomes during periods on statins and periods off statins within each individual, thus adjusting for time-invariant confounders. Non-specific effects of treatment were tested by investigating these outcomes in relation to thiazide diuretic use and antihistamine use in the same cohort.

FINDINGS

The statin-users cohort comprised 1 149 384 individuals, of whom 1 015 949 (88·4%) were aged 50 years or older, 625 616 (54·4%) were male, and 523 768 (45·6%) were female. The study period consisted of 2 053 310 non-treatment periods and 2 997 545 treatment periods, and 957 216 (83·3%) individuals had a medication status change (from on statins to off statins, or vice versa). Suicide outcomes were found in 6372 (0·6%) individuals, depressive disorders in 23 745 (2·1%), anxiety disorders in 30 100 (2·6%), and seizures in 28 844 (2·5%). There were no clear associations between periods of statin treatment and suicidal behaviour or deaths from suicide (hazard ratio 0·99 [95% CI 0·90-1·08]), anxiety disorders (0·99 [0·95-1·02]), or seizures (1·00 [0·97-1·04]). Statins were associated with reduced hazards of depressive disorders (0·91 [0·87-0·94]), which remained after adjustment for concurrent antidepressant use (0·91 [0·88-0·94]). Hazard ratios for depressive disorders were 0·61 (0·38-1·00; n=14 718) with thiazide diuretic use and 0·84 (0·67-1·06; n=23 715) with antihistamine use.

INTERPRETATION

Statin use is not associated with suicidality, anxiety disorders, or seizures. Whether the observed association between statin use and reduced diagnoses of clinical depression is confounded by non-specific benefits related to being prescribed medication needs further research.

FUNDING

Wellcome Trust, Swedish Research Council, National Institute for Health Research (NIHR) Research Professorship, NIHR Oxford Health Biomedical Research Centre, American Foundation for Suicide Prevention, Karolinska Institutet.

Associations between selective serotonin reuptake inhibitors and violent crime in adolescents, young, and older adults - a Swedish register-based study

This study identified individuals ever dispensed a selective serotonin reuptake inhibitor (SSRI) aged 15-60 years during 2006-2013, using Swedish national registers. The outcome was violent crime conviction. The main statistical analyses assessed risks of violent crime during periods on compared to off SSRI treatment within individuals. Further analyses investigated risk over time in relation to treatment initiation and discontinuation. The study identified 785,337 individuals (64.2% female), experiencing 32,203 violent crimes in 5,707,293 person-years. Between-individual analyses found statistically significantly elevated Hazard Ratios (HRs) overall (HR = 1.10), and in 15-24 and 25-34 year-olds (HR = 1.19 and 1.16), but non-significant HRs in 35-44 and 45-60-year-olds (HR = 1.02 and 1.04). In within-individual analyses, where 2.6% of SSRI users were informative, hazards were elevated overall (HR = 1.26, 95% CI = 1.19, 1.34), and across age groups (HR of 1.35 [95% CI = 1.19, 1.54] in 25-34-year-olds to 1.15 [95% CI = 0.99, 1.33] in 35-44-year-olds). In the overall cohort, the within-individual HRs were significantly elevated throughout treatment (HRs of 1.24 to 1.35) and for up to 12 weeks post-discontinuation (HRs of 1.37 and 1.20). While questions on causality remain, these results indicate that there may be an increased risk of violent crime during SSRI treatment in a small group of individuals. It may persist throughout medicated periods, across age groups, and after treatment discontinuation. Further confirmation is needed from studies with different designs, and clinical focus should be on high-risk individuals, as a majority of SSRI-users (around 97% in our cohort) will not commit violent crimes.

Associations between gabapentinoids and suicidal behaviour, unintentional overdoses, injuries, road traffic incidents, and violent crime: population based cohort study in Sweden

OBJECTIVE

To examine associations between gabapentinoids and adverse outcomes related to coordination disturbances (head or body injuries, or both and road traffic incidents or offences), mental health (suicidal behaviour, unintentional overdoses), and criminality.

DESIGN

Population based cohort study.

SETTING

High quality prescription, patient, death, and crime registers, Sweden.

PARTICIPANTS

191 973 people from the Swedish Prescribed Drug Register who collected prescriptions for gabapentinoids (pregabalin or gabapentin) during 2006 to 2013.

MAIN OUTCOME MEASURES

Primary outcomes were suicidal behaviour, unintentional overdoses, head/body injuries, road traffic incidents and offences, and arrests for violent crime. Stratified Cox proportional hazards regression was conducted comparing treatment periods with non-treatment periods within an individual. Participants served as their own control, thus accounting for time invariant factors (eg, genetic and historical factors), and reducing confounding by indication. Additional adjustments were made by age, sex, comorbidities, substance use, and use of other antiepileptics.

RESULTS

During the study period, 10 026 (5.2%) participants were treated for suicidal behaviour or died from suicide, 17 144 (8.9%) experienced an unintentional overdose, 12 070 (6.3%) had a road traffic incident or offence, 70 522 (36.7%) presented with head/body injuries, and 7984 (4.1%) were arrested for a violent crime. In within-individual analyses, gabapentinoid treatment was associated with increased hazards of suicidal behaviour and deaths from suicide (age adjusted hazard ratio 1.26, 95% confidence interval 1.20 to 1.32), unintentional overdoses (1.24, 1.19 to 1.28), head/body injuries (1.22, 1.19 to 1.25), and road traffic incidents and offences (1.13, 1.06 to 1.20). Associations with arrests for violent crime were less clear (1.04, 0.98 to 1.11). When the drugs were examined separately, pregabalin was associated with increased hazards of all outcomes, whereas gabapentin was associated with decreased or no statistically significant hazards. When stratifying on age, increased hazards of all outcomes were associated with participants aged 15 to 24 years.

CONCLUSIONS

This study suggests that gabapentinoids are associated with an increased risk of suicidal behaviour, unintentional overdoses, head/body injuries, and road traffic incidents and offences. Pregabalin was associated with higher hazards of these outcomes than gabapentin.

Antidepressant prescription patterns and CNS polypharmacy with antidepressants among children, adolescents, and young adults: a population-based study in Sweden

This study examines trends in antidepressant drug dispensations among young people aged 0-24 years in Sweden during the period 2006-2013, as well as prescription patterns and central nervous system (CNS) polypharmacy with antidepressants. Using linkage of Swedish national registers, we identified all Swedish residents aged 0-24 years that collected at least one antidepressant prescription (here defined as antidepressant users) between 1 January 2006 and 31 December 2013 (n = 174,237), and categorized them as children (0-11 years), adolescents (12-17 years), and young adults (18-24 years). Prevalence of antidepressant dispensation rose from 1.4 to 2.1% between 2006 and 2013, with the greatest relative increase in adolescents [by 97.8% in males (from 0.6 to 1.3%) and by 86.3% in females (from 1.1 to 2.1%)]. Most individuals across age categories were prescribed selective serotonin reuptake inhibitors, received their prescriptions from psychiatric specialist care, and had treatment periods of over 12 months. Prevalence of CNS polypharmacy (dispensation of other CNS drug classes in addition to antidepressants) increased across age categories, with an overall increase in prevalence from 52.4% in 2006 to 62.1% in 2013. Children experienced the largest increase in polypharmacy of three or more psychotropic drug classes (4.4-10.1%). Anxiolytics, hypnotics, and sedatives comprised the most common additional CNS drug class among persons who were prescribed antidepressants. These findings show that the dispensation of antidepressants among the young is prevalent and growing in Sweden. The substantial degree of CNS polypharmacy in young patients receiving antidepressants requires careful monitoring and further research into potential benefits and harms.

Medications for Alcohol and Opioid Use Disorders and Risk of Suicidal Behavior, Accidental Overdoses, and Crime

OBJECTIVE

The authors examined associations between medications for alcohol and opioid use disorders (acamprosate, naltrexone, methadone, and buprenorphine) and suicidal behavior, accidental overdoses, and crime.

METHOD

In this total population cohort study, 21,281 individuals who received treatment with at least one of the four medications between 2005 and 2013 were identified. Data on medication use and outcomes were collected from Swedish population-based registers. A within-individual design (using stratified Cox proportional hazards regression models) was used to compare rates of suicidal behavior, accidental overdoses, and crime for the same individuals during the period when they were receiving the medication compared with the period when they were not.

RESULTS

No significant associations with any of the primary outcomes were found for acamprosate. For naltrexone, there was a reduction in the hazard ratio for accidental overdoses during periods when individuals received treatment compared with periods when they did not (hazard ratio=0.82, 95% CI=0.70, 0.96). Buprenorphine was associated with reduced arrest rates for all crime categories (i.e., violent, nonviolent, and substance-related) as well as reduction in accidental overdoses (hazard ratio=0.75, 95% CI=0.60, 0.93). For methadone, there were significant reductions in the rate of suicidal behaviors (hazard ratio=0.60, 95% CI=0.40-0.88) as well as reductions in all crime categories. However, there was an increased risk for accidental overdoses among individuals taking methadone (hazard ratio=1.25, 95% CI=1.13, 1.38).

CONCLUSIONS

Medications currently used to treat alcohol and opioid use disorders also appear to reduce suicidality and crime during treatment.

Parental nicotine replacement therapy and offspring bronchitis/bronchiolitis and asthma - a nationwide population-based cohort study

Background

Prior evidence shows that environmental tobacco smoke is a risk factor for respiratory tract infections, wheeze, and asthma. Nicotine replacement therapy has been shown to increase smoking cessation. However, no prior studies have explored if parental use decreases the risk of bronchitis/bronchiolitis and asthma in the offspring.

Objective

To examine whether nicotine replacement therapy varenicline, given to parents, was associated with a reduction in bronchitis/bronchiolitis and/or asthma in their children.

Methods

This study is a population-based cohort study, linking data from nationwide registers, and using a within-individual design that minimizes selection effects and controls for time-invariant confounding factors. Participants included 37,420 parents with a collected prescription of varenicline with 72,392 offspring <18 years of age. Exposure was defined as collected prescriptions of varenicline among the parents. Primary outcomes were offspring hospital visits for bronchitis/bronchiolitis (ICD10: J20 or J21) and offspring hospital visits for asthma (ICD10: J45).

Results

Parental varenicline treatment was associated with a lower rate of visits for bronchitis/bronchiolitis in their children (incidence rate ratio [IRR]=0.67; 95% CI=0.50–0.91), but no association was found for asthma (IRR=1.08; 95% CI=0.97–1.19). The rate reduction of bronchitis/bronchiolitis was similar when we restricted data to children aged 0–3 years (IRR=0.71; 95% CI=0.52–0.97) and to maternal varenicline treatment (IRR=0.64; 95% CI=0.43–0.96). When restricting the outcomes to unplanned visits only (ie, excluding booked appointments, followups, and referrals), no associations were found (IRR=0.72, 95% CI=0.51–1.02).

Conclusion

In this cohort study, nicotine replacement treatment in parents was associated with reduced hospital visits for bronchitis/bronchiolitis in their children.

Benzodiazepine prescribing for children, adolescents, and young adults from 2006 through 2013: A total population register-linkage study

BACKGROUND

Pharmacoepidemiological studies have long raised concerns on widespread use of benzodiazepines and benzodiazepine-related drugs (BZDs), in particular long-term use, among adults and the elderly. In contrast, evidence pertaining to the rates of BZD use at younger ages is still scarce, and the factors that influence BZD utilisation and shape the different prescribing patterns in youths remain largely unexplored. We examined the prevalence rates, relative changes in rates over time, and prescribing patterns for BZD dispensation in young people aged 0-24 years in Sweden during the period January 1, 2006-December 31, 2013, and explored demographic, clinical, pharmacological, and prescriber-related attributes of BZD prescribing in this group.

METHODS AND FINDINGS

Through the linkage of 3 nationwide Swedish health and administrative registers, we collected data on 17,500 children (0-11 years), 15,039 adolescents (12-17 years), and 85,200 young adults (18-24 years) with at least 1 dispensed prescription for a BZD during 2006-2013, out of 3,726,818 Swedish inhabitants aged 0-24 years. Age-specific annual prevalence rates of BZD dispensations were adjusted for population growth, and relative changes in rates were calculated between 2006 and 2013. We analysed how BZD dispensation varied by sex, psychiatric morbidity and epilepsy, concurrent dispensation of psychotropic medication, type of dispensed BZD, and type of healthcare provider prescribing the BZD. Prescribing patterns were established in relation to duration (3 months, >3 to ≤6 months, or >6 months), dosage (<0.5 defined daily dosage [DDD]/day, ≥0.5 to <1.5 DDD/day, or ≥1.5 DDD/day), and "user category" ("regular users" [≥0.5 to <1.5 DDD/day for ≥1 year], "heavy users" [≥1.5 DDD/day for ≥1 year], or otherwise "occasional users"). Multinomial regression models were fitted to test associations between BZD prescribing patterns and individual characteristics of study participants. Between 2006 and 2013, the prevalence rate of BZD dispensation among individuals aged 0-24 years increased by 22% from 0.81 per 100 inhabitants to 0.99 per 100 inhabitants. This increase was mainly driven by a rise in the rate among young adults (+20%), with more modest increases in children (+3%) and adolescents (+7%). Within each age category, overall dispensation of BZD anxiolytics and clonazepam decreased over time, while dispensation of BZD hypnotics/sedatives, including Z-drugs, showed an increase between 2006 and 2013. Out of 117,739 study participants with dispensed BZD prescriptions, 65% initiated BZD prescriptions outside of psychiatric services (92% of children, 60% of adolescents, 60% of young adults), and 76% were dispensed other psychotropic drugs concurrently with a BZD (46% of children, 80% of adolescents, 81% of young adults). Nearly 30% of the participants were prescribed a BZD for longer than 6 months (18% of children, 31% of adolescents, 31% of young adults). A high dose prescription (≥1.5 DDD/day) and heavy use were detected in 2.6% and 1.7% of the participants, respectively. After controlling for potential confounding by demographic and clinical characteristics, the characteristics age above 11 years at the first BZD dispensation, lifetime psychiatric diagnosis or epilepsy, and concurrent dispensation of other psychotropic drugs were found to be associated with higher odds of being prescribed a BZD for longer than 6 months, high dose prescription, and heavy use. Male sex was associated with a higher likelihood of high dose prescription and heavy use, but not with being prescribed a BZD on a long-term basis (> 6 months). The study limitations included lack of information on actual consumption of the dispensed BZDs and unavailability of data on the indications for BZD prescriptions.

CONCLUSIONS

The overall increase in prevalence rates of BZD dispensations during the study period and the unexpectedly high proportion of individuals who were prescribed a BZD on a long-term basis at a young age indicate a lack of congruence with international and national guidelines. These findings highlight the need for close monitoring of prescribing practices, particularly in non-psychiatric settings, in order to build an evidence base for safe and efficient BZD treatment in young persons.

Illicit Drug Use Among Gym-Goers: a Cross-sectional Study of Gym-Goers in Sweden

Background

The use of anabolic-androgenic steroids has increased among gym-goers, and it has been proposed that this may be part of a polysubstance use pattern that includes the use of illicit drugs. Still, epidemiological data on illicit drug use among gym-goers of both genders are meager. The aim of the present study was thus to examine the use of illicit drugs and its correlates in a large sample of men and women who engaged in weight training at gyms across Sweden.

Methods

In this cross-sectional study, a total of 1969 gym-goers who engaged in weight training in 54 gyms across Sweden were invited to fill in a questionnaire. The questionnaire included 25 items on background variables, weight training frequency, use of illicit drugs and doping substances, and non-medical use of benzodiazepines.

Results

Of the gym-goers, 19.6% reported having ever used illicit drugs, 6.5% reported use during the past 12 months, and 2.1% during the past 30 days. The most commonly used drug was cannabis, followed by cocaine, amphetamine, and ecstasy. Almost 40% of those who reported drug use had used more than one drug. Male participants and participants between 20 and 39 years of age made up the majority of users. Furthermore, 5.1% of the reported drug users had ever used a doping substance. There was an almost threefold higher odds (OR = 2.99, 95% CI = 1.16–7.66, p < 0.023) of doping use among people who had reported drug use as compared to non-users.

Conclusions

Training at gyms is typically considered a health-promoting behavior. However, our results revealed a slightly higher prevalence of illicit drug use among gym attendees as compared to the general population. Our findings may have captured an underrecognized group of young adult males who engage in weightlifting and use illicit drugs recreationally and/or as training aids. Developing knowledge is imperative in orientating preventive efforts among at-risk gym-goers.

Trial Registration

ISRCTN11655041

Association Between Deliberate Self-harm and Violent Criminality

IMPORTANCE

Individuals who self-harm may have an increased risk of aggression toward others, but this association has been insufficiently investigated. More conclusive evidence may affect assessment, treatment interventions, and clinical guidelines.

OBJECTIVE

To investigate the association between nonfatal self-harm and violent crime.

DESIGN, SETTING, AND PARTICIPANTS

This population-based longitudinal cohort study, conducted from January 1, 1997, through December 31, 2013, studied all Swedish citizens born between 1982 and 1998 who were 15 years and older (N = 1 850 252). Individuals who emigrated from Sweden before the age of 15 years (n = 104 051) or immigrated to Sweden after the age of 13 years (ie, <2 years before the beginning of the follow-up; n = 22 009) were excluded. Data analysis was performed from April 21, 2016, to June 4, 2016.

EXPOSURES

Receipt of self-harm-associated clinical care.

MAIN OUTCOMES AND MEASURES

Conviction of a violent crime according to the Swedish penal code.

RESULTS

The study cohort consisted of 1 850 525 individuals (950 382 males and 900 143 females), and the mean (SD) follow-up time was 8.1 (4.7) years (range, 0-17.0 years; minimum age, 15 years; maximum age, 32 years). During a mean follow-up period of 8.1 years, 55 185 individuals (3.0%) received clinical care for self-harm. The crude hazard ratio was 4.9 (95% CI, 4.8-5.0) for violent crime conviction in exposed individuals compared with the unexposed group. Women who self-harm were at particularly high risk for expressing violent behaviors. After adjustment for relevant psychiatric comorbidities and socioeconomic status, an almost doubled hazard of violent offense remained (hazard ratio, 1.8; 95% CI, 1.8-1.9).

CONCLUSIONS AND RELEVANCE

Self-harm is associated with an increased risk of conviction for a violent offense in both sexes. The risk of violence, as well as the risk of suicide and self-harm, should be assessed among offending and self-harming individuals.

Subthreshold and threshold attention deficit hyperactivity disorder symptoms in childhood: psychosocial outcomes in adolescence in boys and girls

OBJECTIVE

To examine the association between different levels of childhood attention deficit hyperactivity disorder (ADHD) symptoms and sex differences in psychosocial outcomes during adolescence.

METHOD

Swedish children (n = 4635) were screened for neuropsychiatric symptoms at age 9 or 12. ADHD symptoms were divided into three levels: screen-negative, screen-intermediate, and screen-positive. At follow-up (age 15), parents and teenagers filled out questionnaires regarding (i) hyperactivity/inattention, (ii) peer problems, (iii) school problems, (iv) internalizing problems, (v) antisocial behaviour, (vi) alcohol misuse, and (vii) drug misuse. All outcomes were controlled for symptoms of diagnostic categories other than ADHD.

RESULTS

Increasing levels of ADHD symptoms in childhood were associated with higher proportions of adolescents who displayed negative psychosocial outcomes. More girls than boys reported internalizing problems (all levels) and risky drug use (screen-intermediate and screen-positive only). More boys reported antisocial behaviour at the screen-negative and screen-intermediate levels, but at the screen-positive level, similar proportions of girls and boys displayed antisocial behaviour.

CONCLUSION

The findings support the view that ADHD symptoms, as well as their negative outcomes, are dimensionally distributed in the population and that adolescent girls and boys display different risk profiles. The findings confirm that ADHD symptoms are associated with higher risk of drug misuse in girls.

Effectiveness and implementation of a community-based prevention programme targeting anabolic androgenic steroid use in gyms: study protocol of a quasi-experimental control group study

Background

During the past decades, concerns about increased anabolic androgenic steroid (AAS) use among recreational sportspeople have been raised, yet there is a paucity of AAS prevention efforts targeting this group. Accordingly, doping prevention efforts aimed at gyms have been recommended. The overall objective of the present project is to examine a prevention programme named 100% Pure Hard Training (100% PHT), which targets AAS use among recreational sportspeople training in gyms. Specifically, the project aims to: 1) assess the prevalence of AAS, and its associations with alcohol, illicit drugs, and nutritional supplements use; 2) examine whether 100% PHT can decrease AAS use in gyms, and 3) provide insights into which factors facilitate and/or impede implementation of the programme.

Methods/design

The intervention group consists of 27 gyms, and 27 gyms serve as controls. Intervention gyms take part in 100% PHT, a community-based programme involving several components: (a) training of key stakeholders (i.e., gym staff, gym owners, local police, and municipal prevention coordinators) regarding AAS use; (b) developing an action plan for AAS prevention for each gym; (c) certification of gyms that follow 100% PHT; (d) cooperative relationship between stakeholders; (e) annual follow-up of gyms. The project consists of two studies: Study A will examine the prevalence of AAS use and the effectiveness of 100% PHT (aims 1 and 2), and data for Study A will be collected using questionnaires distributed to gym attendees at two assessment points: baseline (pre-intervention) and follow-up (post-intervention). Study B will evaluate the implementation of 100% PHT (aim 3), and semi-structured interviews with participating stakeholders will be carried out post-intervention.

Discussion

Knowledge gained from the present project can be used to develop community-based doping prevention efforts aimed at recreational sportspeople training in gyms. Furthermore, it can provide insights into which factors are important for successful implementation of AAS prevention programmes that target gyms. Results are also expected to yield information on the prevalence of AAS use as well as associations between the use of AAS and other licit and illicit substances, including nutritional supplements, among recreational sportspeople.

Trial registration

The study was registered retrospectively at isrctn.com (Identifier: ISRCTN11655041; Registration date: 3 November 2016;).

Electronic supplementary material

The online version of this article (doi:10.1186/s13102-016-0062-9) contains supplementary material, which is available to authorized users.

Are offending trajectories identified in population sample studies relevant for treatment settings? A comparison of long-term offending trajectories in individuals treated for substance abuse in adolescence, to a matched general population sample

BACKGROUND

Most studies on offending heterogeneity have been conducted with general population samples. It is not clear to what extent these can inform such outcomes for individuals with substance use disorders specifically.

AIMS

The aim of this study is to compare the offending trajectories of individuals treated for substance use disorders in adolescence with a matched general population sample, and to test for gender differences in this respect.

METHOD

Growth mixture models were applied to identify offending trajectories from age 15 to 33 of 1568 individuals treated for substance use disorders in adolescence, and in a matched population-based sample of 1500 individuals.

RESULTS

Several parallel trajectories for men and for women were identified in both samples. The substance misuse treatment sample, however, had higher levels of offending, larger offender classes, longer careers and two additional, distinct trajectories. Although there were similarities between the men and women, the men were more heterogeneous offenders. There were two distinct offending trajectories among male substance misusers-decreasing high level and decreasing low level offending.

CONCLUSIONS

Differences between substance using and general population samples indicate that results from the latter could underestimate the severity, heterogeneity, and persistence of offending trajectories if merely generalised to individuals with substance use disorders. Our results also indicated that population--based samples might be underpowered for detecting female offending heterogeneity.

Childhood Symptoms of ADHD Overrule Comorbidity in Relation to Psychosocial Outcome at Age 15: A Longitudinal Study

Objective

Neurodevelopmental problems (NDPs) may influence the transition from childhood to adolescence. Our aim was to study long-term psychosocial outcomes of NDPs, focusing on ADHD.

Method

Data was collected through a telephone interview with parents of twins at ages 9 or 12 years. NDP screen-positive children were clinically assessed at age 15; N = 450. Psychosocial outcome concerning peers, school, internalizing problems, antisocial behavior, alcohol misuse, drug misuse, and impaired daily functioning was examined.

Results

Even after controlling for other NDP comorbidity, screen-positivity for ADHD doubled or tripled the odds of later psychosocial problems. When controlling for parental education level, the significant effect of ADHD remained only for antisocial behavior and impaired daily functioning.

Conclusions

Signs of NDPs as well as other psychiatric diagnoses at ages 9 or 12 years are associated with a more problematic adolescence. However, despite the presence of comorbidity, early ADHD symptoms stand out as the most important risk factor for later antisocial development and impaired daily functioning.

Selective Serotonin Reuptake Inhibitors and Violent Crime: A Cohort Study

BACKGROUND

Although selective serotonin reuptake inhibitors (SSRIs) are widely prescribed, associations with violence are uncertain.

METHODS AND FINDINGS

From Swedish national registers we extracted information on 856,493 individuals who were prescribed SSRIs, and subsequent violent crimes during 2006 through 2009. We used stratified Cox regression analyses to compare the rate of violent crime while individuals were prescribed these medications with the rate in the same individuals while not receiving medication. Adjustments were made for other psychotropic medications. Information on all medications was extracted from the Swedish Prescribed Drug Register, with complete national data on all dispensed medications. Information on violent crime convictions was extracted from the Swedish national crime register. Using within-individual models, there was an overall association between SSRIs and violent crime convictions (hazard ratio [HR] = 1.19, 95% CI 1.08-1.32, p < 0.001, absolute risk = 1.0%). With age stratification, there was a significant association between SSRIs and violent crime convictions for individuals aged 15 to 24 y (HR = 1.43, 95% CI 1.19-1.73, p < 0.001, absolute risk = 3.0%). However, there were no significant associations in those aged 25-34 y (HR = 1.20, 95% CI 0.95-1.52, p = 0.125, absolute risk = 1.6%), in those aged 35-44 y (HR = 1.06, 95% CI 0.83-1.35, p = 0.666, absolute risk = 1.2%), or in those aged 45 y or older (HR = 1.07, 95% CI 0.84-1.35, p = 0.594, absolute risk = 0.3%). Associations in those aged 15 to 24 y were also found for violent crime arrests with preliminary investigations (HR = 1.28, 95% CI 1.16-1.41, p < 0.001), non-violent crime convictions (HR = 1.22, 95% CI 1.10-1.34, p < 0.001), non-violent crime arrests (HR = 1.13, 95% CI 1.07-1.20, p < 0.001), non-fatal injuries from accidents (HR = 1.29, 95% CI 1.22-1.36, p < 0.001), and emergency inpatient or outpatient treatment for alcohol intoxication or misuse (HR = 1.98, 95% CI 1.76-2.21, p < 0.001). With age and sex stratification, there was a significant association between SSRIs and violent crime convictions for males aged 15 to 24 y (HR = 1.40, 95% CI 1.13-1.73, p = 0.002) and females aged 15 to 24 y (HR = 1.75, 95% CI 1.08-2.84, p = 0.023). However, there were no significant associations in those aged 25 y or older. One important limitation is that we were unable to fully account for time-varying factors.

CONCLUSIONS

The association between SSRIs and violent crime convictions and violent crime arrests varied by age group. The increased risk we found in young people needs validation in other studies.

Varenicline and risk of psychiatric conditions, suicidal behaviour, criminal offending, and transport accidents and offences: population based cohort study

OBJECTIVE

To examine associations between varenicline and the incidence of a range of adverse outcomes.

DESIGN

Population based cohort study using within person analyses to control for confounding by indication.

SETTING

Whole population of Sweden.

PARTICIPANTS

7,917,436 people aged 15 and over, of whom 69,757 were treated with varenicline between 2006 and 2009.

MAIN OUTCOME MEASURES

Incidence of new psychiatric conditions, suicidal behaviour, suspected and convicted criminal offending, transport accidents, and suspected and convicted traffic offences.

RESULTS

In the whole population, 337,393 new psychiatric conditions were diagnosed during follow-up. In addition, 507,823 suspected and 338,608 convicted crimes, 40,595 suicidal events, 124,445 transport accidents, and 99,895 suspected and 57,068 convicted traffic crimes were recorded. Within person analyses showed that varenicline was not associated with significant hazards of suicidal behaviour, criminal offending, transport accidents, traffic offences, or psychoses. However, varenicline was associated with a small increase in the risk of anxiety conditions (hazard ratio 1.23, 95% confidence interval 1.01 to 1.51) and mood conditions (1.31, 1.06 to 1.63), which was only seen in people with pre-existing psychiatric disorders.

CONCLUSIONS

Concerns that varenicline is associated with an increased risk of many adverse outcomes, including suicidality and accidents, are not supported in this observational study. The small increase in risk of two psychiatric conditions in people with pre-existing psychiatric disorders needs to be confirmed using other research designs.

A study of the possible association between adenosine A2A receptor gene polymorphisms and attention-deficit hyperactivity disorder traits

The adenosine A2A receptor (ADORA2A) is linked to the dopamine neurotransmitter system and is also implicated in the regulation of alertness, suggesting a potential association with attention-deficit hyperactivity disorder (ADHD) traits. Furthermore, animal studies suggest that the ADORA2A may influence ADHD-like behavior. For that reason, the ADORA2A gene emerges as a promising candidate for studying the etiology of ADHD traits. The aim of this study was to examine the relationship between ADORA2A gene polymorphisms and ADHD traits in a large population-based sample. This study was based on the Child and Adolescent Twin Study in Sweden (CATSS), and included 1747 twins. Attention-deficit hyperactivity disorder traits were assessed through parental reports, and samples of DNA were collected. Associations between six single nucleotide polymorphisms (SNPs) and ADHD traits were examined, and results suggested a nominal association between ADHD traits and three of these SNPs: rs3761422, rs5751876 and rs35320474. For one of the SNPs, rs35320474, results remained significant after correction for multiple comparisons. These results indicate the possibility that the ADORA2A gene may be involved in ADHD traits. However, more studies replicating the present results are warranted before this association can be confirmed.

Violent, nonviolent, and substance-related offending over the life course in a cohort of males and females treated for substance misuse as youths

Most studies on adolescent offending heterogeneity are based on general population samples, and few include individuals with substance misuse or look specifically at substance-related offending. It is also unclear how offender subtypes develop after young adulthood or how offending heterogeneity varies between genders. This study aimed to identify subgroups of offending among adolescents with misuse problems and to examine associations with offending in adulthood. The study included 1,992 females and males that consulted a clinic for adolescents with misuse problems between 1968 and 1971. Latent Class Analyses were conducted to identify subgroups based on violent and nonviolent offending before age 20. Participants were then followed until age 50 and reexamined regarding violent, nonviolent, and substance-related crimes. Associations between subgroups before age 20 and subgroups age 21-50 were examined. Before age 20, three subgroups were identified among the females and six among the males. Males were more specialized in their offending and demonstrated higher levels of offending. Results pointed to both stability and decrease of violent and nonviolent offending, and to the emergence of substance-related offending in adulthood in both genders. The connection between substance-related crimes and general delinquency in adulthood among individuals treated for substance misuse suggests that interventions should also address substance misuse for reducing the overall volume of crime. This study also highlights the importance of including females in research on offending heterogeneity.